Embedded flash microcontroller is claimed to be the industry's fastest

Paul Boughton

Renesas Technology Europe is releasing the SH7216 series of 32-bit on-chip flash memory microcontrollers as the latest addition to its successful 32-bit SuperH Risc family. The target market for the SH7216 is industrial applications such as AC servos, factory automation equipment, building automation, air conditioning, and general-purpose networking. The SH7216 group consists of 72 devices offering variations in on-chip memory capacity, package type, and whether or not FPU (floating point processing unit) and/or Ethernet functions are included. The device features 200MHz operating frequency, hence Renesas claims it is the industry's fastest embedded flash microcontroller. It also includes an extensive set of built-in peripherals and communication interfaces.

The main features of this family are summarised below.

SH7216 devices are powered by a 32-bit SH-2A superscalar core. Selected devices also include a 400MFLOPS single- and double-precision floating point unit. Due to the superscalar core that executes two instructions simultaneously, the device can achieve up to 400DMIPS.

The SuperH family has already achieved several industry records. First, it has the best MIPS-to-mm3 ratio, making it 'the fastest MCU in the smallest package.' Second, its 3.75MB flash microcontroller is claimed to be the largest embedded flash device currently available. Third, Renesas says that the new SH7216 offers the fastest performance on the market at 200MHz.

Included is the improved ultra-fast Monos (metal oxide nitride oxide silicon) embedded Flash. This enables fully deterministic zero-wait operation with 10ns access time. The CPU clock runs at 200MHz and is not delayed by flash access, which results in excellent performance with no wait states or cache misses.

The core's CPU registers are now arranged in 'banks' with the 16 registers being mirrored 15 times. Using this technique, a subroutine can use a second set of registers, leaving the current ones ready for use upon return from the subroutine. This means that the registers do not need to be popped onto and back from the stack, providing a quicker return from the subroutine. As a result, the response time to an interrupt request (IRQ) is as quick as a simple branch instruction; at 200MHz this would be 30ns. For inverters and real-time control systems, the combination of a fast core and low reaction time means that the SH7216 provides a level of performance and precision that could previously only be achieved by using an Asic or a dedicated DSP coprocessor.

In addition to the typical serial communication functions, this microcontroller family also features a diverse set of interfaces, including Ethernet, CAN, and USB 2.0. These features eliminate the need for external communication controllers in applications such as office automation equipment and various other types of industrial communication applications. They also give the SH7216 a broader appeal for general purpose connectivity applications.

The SH7216 also includes two advanced motor control timer units (MTU2 and MTU2S) that can control two motors simultaneously and enable multi-axis servo control with high precision. They also include two 12-bit A/D converters that can perform conversions in as little as 1us. This combination of timer and A/D converter makes the SH7216 suitable for controlling brushless AC or brushless DC motors using advanced control techniques.

For more information, visit www.renesas.com